Electron microscope study of the sarcoplasmic reticulum at the Z line level in skeletal muscle fibers of fetal and newborn rats.
D000818:Animals; D000831:Animals, Newborn; D004721:Endoplasmic Reticulum; D005333:Fetus; D008854:Microscopy, Electron; D009132:Muscles / Q000166:cytology*; D051381:Rats